The five-pointed crown displayed on a watch dial is a world-renowned symbol. Around the globe, the Rolex logo marks first-class timepieces and is an unquestionable indicator of a reliable sense of style. Rolex was founded in 1905 and stands for uncompromising quality. The company can proudly look back on a history of influential milestones in the world of watches.
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Since 1948, Omega has been creating watches with a claim to perfection. As the official partner of the Olympic Games and the National Aeronautics and Space Administration (NASA), Omega is the brand of choice for record athletes and astronauts. Even secret agent, James Bond, prefers to sport these classy timepieces. Whether on Earth or on the moon – The diverse collection offered by Omega provides the perfect watch for any mission.
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The winged B logo has always served as a symbol for first-class quality. Generations of pilots have been relying on robust Breitling watches. In water or on land - Breitling is the first choice for admirers of chronometric precision. Founded in 1884, the independent company is one of the most successful brands in the history of the Swiss watch industry.
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With inventiveness and innovation, the International Watch Company has made a name for itself in the Swiss luxury watch industry. Since the establishment of the company in 1868, IWC watches impress with impeccable technology and extraordinary design. For nearly 150 years, IWC has manufactured timepieces that are widely popular in military, aviation, and sports. Admirers of high-quality watches cannot resist the rich tradition and bold innovation that IWC timepieces are universally known for.
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TAG Heuer has distinguished itself as a manufacturer of high-quality timepieces for over 150 years. Intertwined in the world of sports, TAG Heuer has invented iconic instruments for the short-term measurement of time. Furthermore, the brand can boast legendary watch models such as the Carrera or the Monaco – both of which delight watch lovers around the world with a fascinating history and celebrated style.
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Watchmaking from Glashütte: Nomos has combined artisan tradition with modern and bold watch designs for over 25 years. Paradoxically, the timepieces stand out thanks to their minimalist design. Modern and timeless, Nomos watches are universal and elegant mechanisms that can be worn during the everyday.
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The art of fusion: Hublot successfully brings together the art and tradition of horology and innovation. Since 1980, the Swiss company has been manufacturing watches of the highest quality, which stand out due to their extravagant design and exquisite choice in materials. Hublot is highly aware of client needs and therefore continually surpasses expectations with exclusive and luxurious watches.
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Timekeeping as an Art: unlike any other manufacturer, Patek Philippe embodies the continuous and unrestrained quest for watchmaking perfection. The classic timepieces are widely-known for their continual rise in value and are sold at auctions for record-breaking prices. Royals, influentials, and watch enthusiasts gladly choose Patek Philippe to celebrate life and the important milestones that come along with it.
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Audemars Piguet holds a special position in the Swiss watchmaking industry. Independent of large corporations, the company has been producing exquisite watches and movements since 1875. The Audemars Piguet 1972 sports model changed the world of luxury watches and presented one of the most famous watch designs of the century. Today, the Royal Oak is considered to be the flagship model of the Audemars Piguet.
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Longines is a company with a great history. Founded in 1832, the manufacturer has continued to charm watch enthusiasts from all over the world. The current Longines collection reflects the spirit of the company vividly. In addition to modern classics with a sporty flair, Longines also presents timepieces that are committed to a timeless and classic feel.
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They are the jewelers of kings and the king of jewelers – the traditional Parisian company does not only pride itself on its ornate jewelry creations, but on its prestigious watch models as well. Santos, Tank, Ballon Bleu – the diverse collection of watches from Cartier enjoy a distinctive status when it comes to the Universe of watches. Cartier's recipe for success is derived from a first-class quality rating, legendary designs, and a unique history.
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A. Lange & Söhne is a name that embodies superlative timepieces. The exquisite instruments that behold the A. Lange & Söhne name derive from precision, passion, and hard work. The company impressively stays true to traditional watchmaking without the help of large advertising campaigns or marketing activities.
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As an official supplier to the Italian Navy, the watch manufacturer Officine Panerai enjoys a fascinating history. The most famous models from the house are the Radiomir and the Luminor, which, for an extended period of time, belonged among the standard equipment of the Italian frogmen. Since the 1990s, the watches from Panerai have been made available to the market and delight with their striking aesthetics.
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Made in Germany: Sinn Spezialuhren GmbH headquarters resides in Frankfurt am Main. The pilot and flight instructor Helmut Sinn founded the company in 1961. Sinn particularly focuses on the durability and technical excellence of its watches. In addition to everyday wristwatches, Sinn also manufactures specialty watches for professional use.
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Founded in 1904 in Hölstein, Switzerland, the watch company Oris, as one of the few independent private manufacturers, manufactures precise quality watches that enjoy great worldwide recognition. The rotor in striking red color visible through the glass bottom and the designation High Mech are characteristic trademarks of Oris.
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Jaeger-LeCoultre can look back on a long and fascinating history. The watchmaking company has truly earned the title of Manufactory as it has produced several hundreds of movements since its foundation in 1833. With a passion for timekeeping and an unyielding drive for innovation, the company from the Vallée de Joux shines today at the head of the Swiss watchmaking industry.
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The difference between the “Swiss T 25” and “T Swiss T” designations on the bottom of a watch dial

by CHRONEXT

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HomeJournalThe difference between the “Swiss T 25” and “T Swiss T” designations on the bottom of a watch dial

A timely question

March 10. 2016
- by CHRONEXT

Have you ever noticed a difference between the designations located on the bottom of a watch dial? Sometimes they read “Swiss T<25” or “T Swiss T” below the six o’clock marker. But what do these different labels mean? CHRONEXT is here to clear this question right up.

Watches have been created with a luminescent material since the 1900s, rendering them highly legible in unfavourably lit environments. Timepieces are made decipherable in the dark thanks to photoluminescent or radioluminescent properties that coat its hands and indices. Evidently, radioluminescent materials are radioactive, and can thus harm individuals who are exposed to sufficient amounts of it. Therefore, timepieces that utilise a radioluminescent coating on their hands and indices must be regulated to meet specific standards, thus ensuring that the wearers of these watches are exposed to a safe amount of this hazardous material.

Warning: radioluminescent elements

This has not always been the case, though, and in the past, watchmakers have learned the hard way that exposure to large amounts of these materials is deadly. Panerai first developed a process for creating luminous markings in 1915 with the use of the highly toxic based substance Radium. It is likely that Guido Panerai had no idea just how dangerous contact with this substance was. Unfortunately, many of the dial painters from this era eventually died from exposure to the substance.

The highly radioactive Panerai RadiomirJohn Goldberger

Following the revelation that radium was a highly toxic substance, watchmakers turned to tritium to provide a glow to their watches even though it was still a radioluminescent substance. Today, the completely health-friendly photoluminescent Superluminova is used in order to provide optimal legibility of watch dials at all times.

Rolex GMT-Master dial with tritium

The current use of radium has evidently ceased in watch production and has been replaced with much safer alternatives. Today, radioluminescent materials are still used but are typically reserved for professional instruments and are strictly regulated by the standard ISO 3157, which allows two types of radionuclides: tritium and promethium. The use of these materials must be marked on the watch dial.

So what’s the difference?

Rolex “Milsub” Submariner with tritium

T:

A “T” on a watch dial indicates that the watch contains tritium-activated deposits.

Rolex Explorer II Ref. 16570

Swiss-T <25:

This marking means that the watch is Swiss and contains an amount of tritium that emits less than 25 mCi.

Vintage Rolex Day-Date

T Swiss Made T:

This designation again shows that the watch is Swiss but, alternatively, contains an amount of tritium that emits less than 7.5 mCi.

Panerai Luminor PAM00561

L Swiss Made L:

When you see the designation “L Swiss Made L” on a watch dial, you can be sure that the lume material is photoluminescent.

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by CHRONEXT

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